Cryopump system and monitoring method thereof

ABSTRACT

A cryopump system mounted on a vacuum process device, the cryopump system including at least one cryopump, a cryopump controller that controls the cryopump, a network that connects the cryopump to the cryopump controller and transmits information related to the cryopump between the cryopump and the cryopump controller, and a cryopump monitor that is connected to the network and displays the information related to the cryopump, which is transmitted via the network, in which the cryopump controller is disposed in a casing of the vacuum process device, and the cryopump monitor is disposed outside the casing of the vacuum process device.

RELATED APPLICATIONS

The content of Japanese Patent Application No. 2020-194876, on the basisof which priority benefits are claimed in an accompanying applicationdata sheet, is in its entirety incorporated herein by reference.

BACKGROUND Technical Field

Certain embodiments of the present invention relate to a cryopump systemand a monitoring method thereof.

Description of Related Art

A cryopump is a vacuum pump that captures gas molecules throughcondensation and/or adsorption on a cryopanel cooled to a cryogenictemperature and exhausts the gas molecules. The cryopump is mounted on avacuum process device in order to realize a clean vacuum environmentrequired for semiconductor circuit manufacturing processes.

SUMMARY

According to an aspect of the present invention, there is provided acryopump system mounted on a vacuum process device. The cryopump systemincludes at least one cryopump, a cryopump controller that controls thecryopump, a network that connects the cryopump to the cryopumpcontroller and transmits information related to the cryopump between thecryopump and the cryopump controller, and a cryopump monitor that isconnected to the network and displays the information related to thecryopump, which is transmitted via the network. The cryopump controlleris disposed in a casing of the vacuum process device, and the cryopumpmonitor is disposed outside the casing of the vacuum process device.

According to another aspect of the present invention, there is provideda method of monitoring a cryopump system mounted on a vacuum processdevice. The cryopump system includes at least one cryopump, a cryopumpcontroller that is disposed in a casing of the vacuum process device andcontrols the cryopump, and a network that connects the cryopump to thecryopump controller and transmits information related to the cryopumpbetween the cryopump and the cryopump controller. The method includesconnecting a cryopump monitor to the network and disposing the cryopumpmonitor outside the casing of the vacuum process device and displayingthe information related to the cryopump, which is transmitted via thenetwork, on the cryopump monitor.

Any combination of the components described above and a combinationobtained by switching the components and expressions of the presentinvention between methods, devices, and systems are also effective as anaspect of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view showing a cryopump system according to anembodiment.

FIG. 2 is a schematic view showing an example of a cryopump that can beused in the cryopump system according to the embodiment.

FIG. 3 is a schematic view showing an example of a compressor that canbe used in the cryopump system according to the embodiment.

FIG. 4 is a schematic view showing an example of a cryopump monitor thatcan be used in the cryopump system according to the embodiment.

DETAILED DESCRIPTION

The present inventors have studied a cryopump system mounted on a vacuumprocess device and have come to recognize the following problems. Itwould be convenient if information related to a cryopump can be seenduring the operation of the vacuum process device. Such information isparticularly useful, when an abnormality occurs, in identifying a causeof the abnormality and returning to a normal state. Thus, a plan tointegrally incorporate a display unit that displays information into thecryopump is conceivable. However, even in such a case, in reality,information cannot be seen during operation in many cases. This isbecause even when the display unit is provided, the display unit ishidden at a place that cannot be seen from the outside in most cases asthe cryopump is housed in the vacuum process device. In addition, forsafety reasons such as avoiding contact with dangers such as a highvoltage and a high energy beam used in the vacuum process device,internal components of the vacuum process device, such as the cryopump,are required to be physically inaccessible to humans during theoperation of the vacuum process device. When the operation of the vacuumprocess device is stopped, the display unit can be seen by approachingthe cryopump, but the operation stop of the device is not desirablesince the operation stop causes a decrease in productivity.

It is desirable to provide a cryopump system in which informationrelated to the cryopump can be easily confirmed during the operation ofthe vacuum process device.

Hereinafter, an embodiment for carrying out the present invention willbe described in detail with reference to the drawings. In thedescription and drawings, the same or equivalent components, members,and processing will be assigned with the same reference symbols, andredundant description thereof will be omitted as appropriate. The scalesand shapes of the shown parts are set for convenience in order to makethe description easy to understand, and are not to be understood aslimiting unless stated otherwise. The embodiment is merely an exampleand does not limit the scope of the present invention. Allcharacteristics and combinations to be described in the embodiment arenot necessarily essential to the invention.

FIG. 1 is a schematic view showing a cryopump system 100 according tothe embodiment. The cryopump system 100 is mounted on a vacuum processdevice 200 and is used in order to evacuate a vacuum chamber 202 of thevacuum process device 200 to a desired degree of vacuum. The vacuumprocess device 200 is configured to process an object to be processed,such as a wafer, in a vacuum environment in the vacuum chamber 202through a desired vacuum process. The vacuum process device 200 may be,for example, an ion implanter, a sputtering device, a vapor depositiondevice, or other vacuum process device.

The vacuum process device 200 includes a host controller 204 and acasing 206, in addition to the vacuum chamber 202. The host controller204 is configured to control communication between the vacuum processdevice 200 and the cryopump system 100. The host controller 204 may beconfigured as a control device that controls the vacuum process device200, or may configure a part of such a control device. The casing 206forms the exterior of the vacuum process device 200, and houses variouscomponents of the vacuum process device 200. The vacuum chamber 202 andthe host controller 204 are disposed in the casing 206.

The casing 206 may be an enclosure that covers the entire surface of thevacuum process device 200. The casing 206 may include a frame structurein which the components of the vacuum process device 200 are providedand which supports the components, a panel member which partitions theinside of the vacuum process device 200 from the outside, and a doorwhich can be opened and closed for accessing the inside of the vacuumprocess device 200 from the outside. The panel member and the door maybe mounted on the frame structure. The casing 206 may include aradiation shielding material such as lead in order to prevent radiation,which can be generated by the vacuum process device 200, from leaking tothe outside.

Alternatively, the casing 206 may not cover the entire surface of thevacuum process device 200. A part of the casing 206 may be opened, and apart of the vacuum process device 200 may be seen from the outside.

The cryopump system 100 includes at least one cryopump 10, at least onecompressor 12, a cryopump controller 110, a network 120, and a cryopumpmonitor 130.

The cryopump 10 is mounted to the vacuum chamber 202 in order toevacuate the vacuum chamber 202 of the vacuum process device 200.Accordingly, the cryopump 10 is disposed in the casing 206 of the vacuumprocess device 200 together with the vacuum chamber 202. An exemplaryconfiguration of the cryopump 10 that can be used in the cryopump system100 according to the embodiment will be described later with referenceto FIG. 2.

The compressor 12 is provided in order to supply and discharge arefrigerant gas to an expander (to be described later) provided in thecryopump 10. The compressor 12 is connected to the expander of thecryopump 10 by a gas line 13, and is disposed outside the casing 206 ofthe vacuum process device 200. The gas line 13 includes a high pressureline 13 a that connects the compressor 12 to the expander such that therefrigerant gas is supplied from the compressor 12 to the expander and alow pressure line 13 b that connects the compressor 12 to the expandersuch that the refrigerant gas is collected from the expander to thecompressor 12. An exemplary configuration of the compressor 12 that canbe used in the cryopump system 100 according to the embodiment will bedescribed later with reference to FIG. 3.

In the cryopump system 100, a plurality of cryopumps 10, for example,several to tens of cryopumps 10 or more may be provided. In addition, inorder to supply and discharge the refrigerant gas to the cryopumps 10, aplurality of compressors 12 may be provided in the cryopump system 100.

The cryopump controller 110 is configured to control the cryopump system100 in a comprehensive manner based on a command received from the hostcontroller 204. In addition, the cryopump controller 110 is configuredto transmit information related to the cryopump system 100 to the hostcontroller 204. Accordingly, the cryopump controller 110 can control thecryopump 10 and the compressor 12 based on the command from the hostcontroller 204, and can transmit information related to the cryopump 10and information related to the compressor 12 to the host controller 204.

The cryopump controller 110 is connected to the host controller 204 by afirst communication line 208 so as to be able to communicate therewith.The first communication line 208 may be a communication cable such asRS-232C. Similar to the host controller 204, the cryopump controller 110is disposed in the casing 206 of the vacuum process device 200.

The internal configuration of the cryopump controller 110 is realized byan element or a circuit including a CPU and a memory of a computer as ahardware configuration and is realized by a computer program as asoftware configuration, but is shown in the drawings as a functionalblock realized in cooperation therewith. It is clear for those skilledin the art that the functional blocks can be realized in various mannersin combination with hardware and software. For example, the cryopumpcontroller 110 can be mounted in combination with a processor (hardware)such as a central processing unit (CPU) and a microcomputer and asoftware program executed by the processor (hardware).

The network 120 connects the cryopump 10 to the cryopump controller 110so as to be able to communicate with each other. The cryopump system 100transmits information related to the cryopump 10 between the cryopump 10and the cryopump controller 110 via the network 120. The cryopump 10 isconnected to the cryopump controller 110 by a second communication line122. The second communication line 122 may be a communication cable suchas RS-485.

The network 120 further connects the compressor 12 to the cryopumpcontroller 110 so as to be able to communicate with each other. Thecryopump system 100 transmits information related to the compressor 12between the compressor 12 and the cryopump controller 110 via thenetwork 120. The compressor 12 is connected to the cryopump controller110 by a third communication line 123. The third communication line 123may be a communication cable such as RS-485.

The cryopump monitor 130 is connected to the network 120 and isconfigured to display information related to the cryopump 10, which istransmitted via the network 120. In addition thereto or instead thereof,the cryopump monitor 130 may be configured to display informationrelated to the compressor 12 transmitted via the network 120.

The cryopump monitor 130 is connected to the network 120 without goingthrough the host controller 204. That is, the cryopump monitor 130 isconfigured so as not to communicate with the host controller 204 of thevacuum process device 200. In the embodiment, the cryopump monitor 130is connected to the cryopump controller 110 by a fourth communicationline 124. The fourth communication line 124 may be a communication cablesuch as RS-485.

The cryopump monitor 130 is disposed outside the casing 206 of thevacuum process device 200. The cryopump monitor 130 is disposed at aplace separated from the casing 206. In the embodiment, the cryopumpmonitor 130 is provided in the compressor 12 or in the vicinity thereof.The cryopump monitor 130 may be detachably mounted on the compressor 12.Alternatively, the cryopump monitor 130 may be provided on a monitorprovision surface provided in the vicinity of the compressor 12. Themonitor provision surface may be, for example, a wall surface in thevicinity of the compressor 12, or the surface of a device in thevicinity of the compressor 12. The cryopump monitor 130 may beconfigured as a device that can be carried by a worker.

An exemplary configuration of the cryopump monitor 130 that can be usedin the cryopump system 100 according to the embodiment will be describedlater with reference to FIG. 4.

FIG. 2 is a schematic view showing an example of the cryopump 10 thatcan be used in the cryopump system 100 according to the embodiment. Thecryopump 10 includes an expander 14, a cryopump container 16, aradiation shield 18, and a cryopanel 20. In addition, the cryopump 10includes a pressure sensor 21, a rough valve 24, a purge valve 26, and avent valve 28, and the components are provided in the cryopump container16.

The compressor 12 is configured to collect a refrigerant gas from theexpander 14, to pressurize the collected refrigerant gas, and to supplythe refrigerant gas to the expander 14 again. The expander 14 is alsocalled a cold head, and configures a cryocooler together with thecompressor 12. The expander 14 is also called a “cryocooler” in somecases. A thermodynamic cycle, through which chill is generated, isconfigured by performing circulation of the refrigerant gas between thecompressor 12 and the expander 14 with an appropriate combination ofpressure fluctuations and volume fluctuations of the refrigerant gas inthe expander 14, and thereby the expander 14 can provide cryogenictemperature cooling. Although the refrigerant gas is typically a heliumgas, other appropriate gases may be used. In order to facilitateunderstanding, a direction in which the refrigerant gas flows is shownwith an arrow in FIG. 1. Although the cryocooler is, for example, atwo-stage Gifford-McMahon (GM) cryocooler, the cryocooler may be a pulsetube cryocooler, a Stirling cryocooler, or other types of cryocoolers.

The cryopump container 16 is a vacuum chamber that is designed tomaintain vacuum during evacuate operation of the cryopump 10 and towithstand a pressure in the ambient environment (for example, theatmospheric pressure). The cryopump container 16 includes a cryopanelaccommodation unit 16 a including an intake port 17 and a cryocooleraccommodation unit 16 b. The cryopanel accommodation unit 16 a has adome shape in which the intake port 17 is opened and an opposite sidethereof is closed, and the radiation shield 18 and the cryopanel 20 areaccommodated therein together. The cryocooler accommodation unit 16 bhas a cylindrical shape, and has one end fixed to a room temperatureportion of the expander 14 and the other end connected to the cryopanelaccommodation unit 16 a. The expander 14 is inserted therein. Inaddition, the pressure sensor 21 measures a pressure in the cryopumpcontainer 16.

The radiation shield 18 is thermally coupled to a first cooling stage ofthe expander 14, and is cooled to a first cooling temperature (forexample, 80 K to 120 K). The cryopanel 20 is thermally coupled to asecond cooling stage of the expander 14, and is cooled to a secondcooling temperature (for example, 10 K to 20 K) lower than the firstcooling temperature. The radiation shield 18 is disposed in the cryopumpcontainer 16 to surround the cryopanel 20, and shields against inputheat from the cryopump container 16 and the ambient environment to thecryopanel 20. A gas that enters from the intake port 17 of the cryopump10 is captured through condensation or adsorption in the cryopanel 20.In addition, a first temperature sensor 22 that measures the temperatureof the radiation shield 18 and a second temperature sensor 23 thatmeasures the temperature of the cryopanel 20 are provided in thecryopump container 16. Since various known configurations can be adoptedas appropriate as configurations of the cryopump 10, such as thedispositions and shapes of the radiation shield 18 and the cryopanel 20,description thereof will not be made in detail herein.

The rough valve 24 is attached to the cryopump container 16, forexample, the cryocooler accommodation unit 16 b. The rough valve 24 isconnected to a rough pump (not shown) provided outside the cryopump 10.The rough pump is a vacuum pump for evacuating the cryopump 10 to anoperation starting pressure thereof. Through control by the cryopumpcontroller 110, the cryopump container 16 communicates with the roughpump when the rough valve 24 is opened, and the cryopump container 16 iscut off from the rough pump when the rough valve 24 is closed. Byopening the rough valve 24 and operating the rough pump, the cryopump 10can be decompressed.

The purge valve 26 is attached to the cryopump container 16, forexample, to the cryopanel accommodation unit 16 a. The purge valve 26 isconnected to a purge gas supply device (not shown) provided outside thecryopump 10. Through control by the cryopump controller 110, a purge gasis supplied to the cryopump container 16 when the purge valve 26 isopened, and the purge gas supply to the cryopump container 16 is cut offwhen the purge valve 26 is closed. The purge gas may be, for example, anitrogen gas or other dry gases. The temperature of the purge gas may beadjusted, for example, to the room temperature, or may be heated to atemperature higher than the room temperature. By opening the purge valve26 and introducing the purge gas into the cryopump container 16, thecryopump 10 can be pressurized. In addition, the temperature of thecryopump 10 can be increased from a cryogenic temperature to the roomtemperature or a temperature higher than the room temperature.

The vent valve 28 is attached to the cryopump container 16, for example,the cryocooler accommodation unit 16 b. The vent valve 28 is provided inorder to exhaust a fluid from the inside of the cryopump 10 to theoutside. The fluid exhausted from the vent valve 28 is basically a gas,but may be a liquid or a mixture of a gas and a liquid. The vent valve28 can be opened and closed through control by the cryopump controller110. Along with this, the vent valve 28 can be mechanically opened by adifferential pressure inside and outside the cryopump container 16. Whenan excessive pressure is generated in the cryopump container 16, thevent valve 28 is configured to also function as a safety valve forreleasing the pressure to the outside.

In addition, the expander 14 is provided with a variable speed expandermotor 30 that drives the expander 14. The expander motor 30 includes aninverter, and can change a motor operating frequency through control bythe cryopump controller 110.

The cryopump controller 110 may control the expander motor 30 based onthe cooling temperature of the radiation shield 18 (or the cryopanel 20)in the evacuate operation of the cryopump 10. For example, the cryopumpcontroller 110 may control the operating frequency of the expander motor30 such that the cooling temperature of the radiation shield 18 isconstant.

In addition, in regeneration operation of the cryopump 10, the cryopumpcontroller 110 may control the rough valve 24, the purge valve 26, thevent valve 28, and the expander motor 30 based on a pressure in thecryopump container 16 (or if necessary, based on the temperature of thecryopanel 20 and the pressure in the cryopump container 16).

The cryopump 10 includes an input and output circuit 32 that putstransmission and reception between the cryopump 10 and the cryopumpcontroller 110 together. The input and output circuit 32 may be, forexample, an I/O module or a remote I/O unit. The input and outputcircuit 32 is electrically connected to each of devices of the cryopump10, such as the pressure sensor 21, the first temperature sensor 22, thesecond temperature sensor 23, the rough valve 24, the purge valve 26,the vent valve 28, and the expander motor 30 to transmit and receive asignal to and from each of the devices. In addition, the input andoutput circuit 32 is connected to the cryopump controller 110 by thesecond communication line 122 so as to be able to communicate therewith.

Therefore, the cryopump 10 transmits a measured pressure signalindicating a measured pressure in the cryopump container 16 from thepressure sensor 21 to the cryopump controller 110 via the input andoutput circuit 32 (and the second communication line 122). The cryopump10 transmits a measured temperature signal indicating a measuredtemperature from each of the first temperature sensor 22 and the secondtemperature sensor 23 to the cryopump controller 110 via the input andoutput circuit 32. In addition, the cryopump 10 transmits a valve statesignal indicating the open or closed state of each valve (that is, therough valve 24, the purge valve 26, and the vent valve 28) to thecryopump controller 110 via the input and output circuit 32. Thecryopump 10 transmits a motor state signal indicating the on or offstate and operating frequency of the expander motor 30 to the cryopumpcontroller 110 via the input and output circuit 32.

In addition, the cryopump 10 receives a valve control signal from thecryopump controller 110, which indicates an operation command to eachvalve, with the input and output circuit 32, and the input and outputcircuit 32 transmits the valve control signal to a corresponding valve.The valve which has received the valve control signal is opened andclosed in accordance with the valve control signal. Similarly, thecryopump 10 receives a motor control signal from the cryopump controller110, which indicates an operation command to the expander motor 30, withthe input and output circuit 32, and the input and output circuit 32transmits the motor control signal to the expander motor 30. Theexpander motor 30 is turned on and off or an operating frequency iscontrolled in accordance with the motor control signal.

In the embodiment, each cryopump 10 is not provided with a display unitsuch as a liquid crystal panel and a monitor that display informationrelated to the cryopump 10, such as a measured pressure, a measuredtemperature, and the operation state of each valve or the expander motor30.

FIG. 3 is a schematic view showing an example of the compressor 12 thatcan be used in the cryopump system 100 according to the embodiment. Thecompressor 12 includes a high pressure gas outlet 50, a low pressure gasinlet 51, a high pressure flow path 52, a low pressure flow path 53, afirst pressure sensor 54, a second pressure sensor 55, a bypass line 56,a compressor main body 57, and a compressor casing 58.

The high pressure gas outlet 50 is provided in the compressor casing 58as a working gas discharge port of the compressor 12, and the lowpressure gas inlet 51 is provided in the compressor casing 58 as aworking gas suction port of the compressor 12. The high pressure line 13a is connected to the high pressure gas outlet 50, and the low pressureline 13 b is connected to the low pressure gas inlet 51. The highpressure flow path 52 connects a discharge port of the compressor mainbody 57 to the high pressure gas outlet 50, and the low pressure flowpath 53 connects the low pressure gas inlet 51 to a suction port of thecompressor main body 57. The compressor casing 58 accommodates the highpressure flow path 52, the low pressure flow path 53, the first pressuresensor 54, the second pressure sensor 55, the bypass line 56, and thecompressor main body 57. The compressor 12 is also called a compressorunit.

The compressor main body 57 is configured to internally compress theworking gas sucked from the suction port and to discharge the workinggas from the discharge port. The compressor main body 57 may be, forexample, a scroll type pump, a rotary type pump, or other pumps thatpressurize the working gas. The compressor main body 57 may include avariable speed compressor motor 57 a. The compressor motor 57 a includesan inverter, and can change a motor operating frequency through controlby the cryopump controller 110. In this manner, the compressor main body57 may be configured to change the flow rate of the working gas to bedischarged. Alternatively, the compressor main body 57 may be configuredto discharge the working gas at a fixed and constant flow rate. Thecompressor main body 57 is called a compression capsule in some cases.

The first pressure sensor 54 is disposed in the high pressure flow path52 to measure the pressure of the working gas flowing in the highpressure flow path 52. The second pressure sensor 55 is disposed in thelow pressure flow path 53 to measure the pressure of the working gasflowing in the low pressure flow path 53. Accordingly, the firstpressure sensor 54 and the second pressure sensor 55 can also be calleda high pressure sensor and a low pressure sensor, respectively.

The bypass line 56 connects the high pressure flow path 52 to the lowpressure flow path 53 such that the working gas bypasses the expander 14and returns from the high pressure flow path 52 to the low pressure flowpath 53. A relief valve 60 for opening and closing the bypass line 56 orcontrolling the flow rate of the working gas flowing in the bypass line56 is provided in the bypass line 56. The relief valve 60 is configuredto open when a differential pressure that is equal to or higher than aset pressure acts between an inlet and an outlet thereof. The reliefvalve 60 may be an on/off valve or a flow rate control valve, or may be,for example, a solenoid valve. It is possible to set the set pressure asappropriate based on empirical knowledge of a designer or experimentsand simulations by the designer. Accordingly, a differential pressurebetween the high pressure line 13 a and the low pressure line 13 b canbe prevented from exceeding the set pressure and becoming excessive.

For example, the relief valve 60 may be opened and closed under thecontrol of the cryopump controller 110. The cryopump controller 110 maycompare a measured differential pressure between the high pressure line13 a and the low pressure line 13 b to the set pressure, and control therelief valve 60 such that the relief valve 60 is opened in a case wherethe measured differential pressure is equal to or higher than the setpressure, and the relief valve 60 is closed in a case where the measureddifferential pressure is lower than the set differential pressure. Thecryopump controller 110 may acquire the measured differential pressurebetween the high pressure line 13 a and the low pressure line 13 b frommeasured pressures from the first pressure sensor 54 and the secondpressure sensor 55. As another example, the relief valve 60 may beconfigured to operate as a so-called safety valve, that is, may bemechanically opened when the differential pressure that is equal to orhigher than the set pressure acts between the inlet and the outlet.

In addition, in the embodiment, the compressor 12 includes an operationpanel 62 for operating the compressor 12. The operation panel 62 isprovided in the compressor casing 58. The operation panel 62 is providedwith an operation unit 63, a control unit 64, and a display unit 65. Theoperation unit 63 includes input means such as an operation button thatreceives the operation of the compressor 12 by an operator. The controlunit 64 is housed inside the operation panel 62, and controls each ofdevices of the compressor 12, such as the compressor main body 57(compressor motor 57 a) and the relief valve 60, in response to theoperation of the operation unit 63. The display unit 65 is controlled bythe control unit 64, and displays information related to the compressor12.

The control unit 64 of the compressor 12 can also operate as an inputand output circuit (for example, an I/O module or a remote I/O unit)that puts transmission and reception between the compressor 12 and thecryopump controller 110 together. Therefore, the control unit 64 iselectrically connected to each of devices of the compressor 12, such asthe first pressure sensor 54, the second pressure sensor 55, thecompressor main body 57 (compressor motor 57 a), and the relief valve 60to transmit and receive a signal to and from each of the devices. Inaddition, the control unit 64 is connected to the cryopump controller110 by the third communication line 123 so as to be able to communicatetherewith.

Therefore, the compressor 12 transmits a measured pressure signalindicating a measured pressure from each of the first pressure sensor 54and the second pressure sensor 55 to the cryopump controller 110 via thecontrol unit 64. In addition, the compressor 12 transmits a motor statesignal indicating the on or off state and operating frequency of thecompressor motor 57 a and a valve state signal indicating the open orclosed state or opening degree of the relief valve 60 to the cryopumpcontroller 110 via the control unit 64.

In addition, the compressor 12 receives a motor control signal from thecryopump controller 110, which indicates an operation command to thecompressor motor 57 a, with the control unit 64, and the control unit 64transmits the motor control signal to the compressor motor 57 a. Thecompressor motor 57 a is turned on and off or an operating frequency iscontrolled in accordance with the motor control signal. Similarly, thecompressor 12 receives a valve control signal from the cryopumpcontroller 110, which indicates an operation command to the relief valve60, with the control unit 64, and the control unit 64 transmits thevalve control signal to the relief valve 60. The relief valve 60 isopened and closed in accordance with the valve control signal.

The compressor 12 can include other various components. For example, anoil separator or an adsorber may be provided in the high pressure flowpath 52. A storage tank and other components may be provided in the lowpressure flow path 53. In addition, an oil circulation system that coolsthe compressor main body 57 with an oil and a cooling system that coolsthe oil with cooling water may be provided in the compressor 12.

FIG. 4 is a schematic view showing an example of the cryopump monitor130 that can be used in the cryopump system 100 according to theembodiment. The cryopump monitor 130 includes an operation unit or panel132, an input and output circuit 134, and a display unit 136.

The operation unit 132 includes input means such as various types ofoperation buttons for receiving an operation of the cryopump system 100(for example, the cryopump 10 and the compressor 12) by the operator.The operation unit 132 is electrically connected to the input and outputcircuit 134 to transmit an operation signal indicating the operation ofthe operation unit 132 to the input and output circuit 134. The cryopumpcontroller 110 receives the operation signal via the input and outputcircuit 134 (and the fourth communication line 124) and controls thecryopump 10 (or the compressor 12) in accordance with the operationsignal. In this example, the operation unit 132 is provided in a lowerportion of the cryopump monitor 130.

The input and output circuit 134 is housed inside the cryopump monitor130 and is connected to the cryopump controller 110 by the fourthcommunication line 124 so as to be able to communicate therewith. Theinput and output circuit 134 may be, for example, an I/O module or aremote I/O unit. The fourth communication line 124 may be connected to aconnector provided at the cryopump monitor 130 and be connected to theinput and output circuit 134 via the connector.

The display unit 136 is electrically connected to the input and outputcircuit 134 to receive a signal indicating information related to thecryopump 10 and/or information related to the compressor 12 from theinput and output circuit 134. The display unit 136 displays theinformation related to the cryopump 10 and/or the compressor 12 based onthe signal received by the input and output circuit 134 from thecryopump controller 110. For example, the display unit 136 includes adisplay panel unit 136 a and an indicator light unit 136 b. The displaypanel unit 136 a may be, for example, a liquid crystal panel or otherdisplay devices that can display a number, text, a signal indicating theinformation related to the cryopump 10 and/or the compressor 12. Theindicator light unit 136 b may be, for example, an LED lamp or otherindicators that are turned on and off to indicate the informationrelated to the cryopump 10 and/or the compressor 12. In this example,the display unit 136 is provided in an upper portion of the cryopumpmonitor 130.

Examples of the information related to the cryopump 10 that can bedisplayed on the display unit 136 include the following, and are notlimited thereto.

-   -   Current measured values from sensors mounted on the cryopump 10        (for example, the measured pressure of the pressure sensor 21,        the measured temperature of the first temperature sensor 22, and        the measured temperature of the second temperature sensor 23)    -   Current operation states of devices mounted on the cryopump 10        (for example, the open or closed state of the rough valve 24,        the open or closed state of the purge valve 26, the open or        closed state of the vent valve 28, the on or off state of the        expander motor 30 (that is, the on or off state of the cryopump        10), and the operating frequency of the expander motor 30)    -   Operating history of the cryopump 10 (for example, the operating        duration of the cryopump 10, elapsed time from regeneration        start of the cryopump 10, the number of times of regeneration        completion of the cryopump 10, alarm related to the cryopump 10,        which is generated during the operation of the cryopump 10,        communication time between the cryopump 10 and the cryopump        controller 110, past measured values from sensors mounted on the        cryopump 10, and past operation states of devices mounted on the        cryopump 10)    -   Internal parameters of the cryopump 10 (for example, set cooling        temperatures of the radiation shield 18 and the cryopanel 20 for        performing the evacuate operation of the cryopump 10, control        parameters (for example, control gain for PID control) for        adjusting the temperature of the radiation shield 18 (or the        cryopanel 20), and various types of regeneration parameters that        define terms and conditions such as the temperature, pressure,        and opening and closing timing of each valve for performing the        regeneration of the cryopump 10)    -   Other parameters related to the cryopump 10 (for example, the        serial number of the cryopump 10)    -   Various types of commands for operating the cryopump 10

In addition, examples of information related to the compressor 12 thatcan be displayed on the display unit 136 include the following, and arenot limited thereto.

-   -   Current measured values from sensors mounted on the compressor        12 (for example, the measured pressure of the first pressure        sensor 54, the measured pressure of the second pressure sensor        55, and a differential pressure between measured pressures from        the first pressure sensor 54 and the second pressure sensor 55)    -   Current operation states of devices mounted on the compressor 12        (the set valve of a differential pressure between the high        pressure flow path 52 and the low pressure flow path 53, the on        or off state of the compressor motor 57 a (that is, the on or        off state of the compressor 12), the operating frequency of the        compressor motor 57 a, the open or closed state or opening        degree of the relief valve 60, and the flow rate of cooling        water that cools the compressor main body 57)    -   The operating history of the compressor 12 (the operating        duration of the compressor 12, the use time of the adsorber,        alarm related to the compressor 12, which is generated during        the operation of the compressor 12, past measured values from        sensors mounted on the compressor 12, and past operation states        of devices mounted on the compressor 12)    -   Internal parameters of the compressor 12    -   Other parameters related to the compressor 12    -   Various types of commands for operating the compressor 12

The cryopump monitor 130 may include a storage unit such as alarge-capacity storage, or may be connectable to an external storagedevice. Past measured values and operation states of the cryopump system100 or other information that can be displayed may be accumulated in thestorage unit or the storage device, be made accessible from the cryopumpmonitor 130 if necessary, and be displayed on the cryopump monitor 130.

In addition, the cryopump monitor 130 may visually present informationand present the information audibly or by other means.

A monitoring method of the cryopump system 100 according to theembodiment includes connecting the cryopump monitor 130 to the network120 and disposing the cryopump monitor outside the casing 206 of thevacuum process device 200. For example, the cryopump monitor 130 isconnected to the cryopump controller 110 using the fourth communicationline 124. Accordingly, the cryopump monitor 130 is connected to thenetwork 120 and is disposed outside the casing 206 of the vacuum processdevice 200. Since the cryopump controller 110 is disposed in the casing206 of the vacuum process device 200, it can be difficult to performconnection between the cryopump monitor 130 and the cryopump controller110 during the operation of the cryopump system 100 (that is, during theoperation of the vacuum process device 200). Accordingly, it ispreferable to perform connecting work of the cryopump monitor 130 beforethe operation of the cryopump system 100.

The monitoring method of the cryopump system 100 further includesdisplaying information related to the cryopump 10, which is transmittedvia the network 120, on the cryopump monitor 130. In addition, themethod may include displaying information related to the compressor 12,which is transmitted via the network 120, on the cryopump monitor 130.These types of display may be performed during the operation of thecryopump system 100 or may be performed during the operation stop of thecryopump system 100.

As described above, all of the information related to the cryopump 10and the information related to the compressor 12 are put together in thecryopump controller 110 in the cryopump system 100. The network 120 usedin communication in the cryopump system 100 is configured to broadcastcommunication data (including the information related to the cryopump 10(or the compressor 12)) to all nodes, for example, like RS-485.Therefore, by connecting the cryopump monitor 130 to the network 120(for example, the cryopump controller 110), the cryopump monitor 130 canacquire (so to speak, intercept) communication data transmitted betweenthe cryopump controller 110 and the cryopump 10 (or the compressor 12)via the network 120. In this manner, the cryopump monitor 130 candisplay the information related to the cryopump 10 (or the compressor12) based on the acquired communication data.

The monitoring method of the cryopump system 100 may further includecontrolling the cryopump system 100 in accordance with the operation ofthe cryopump monitor 130. As described above, the cryopump controller110 can receive an operation signal generated as the operator operatesthe operation unit 132 via the input and output circuit 134 (and thefourth communication line 124) and control the cryopump 10 (or thecompressor 12) in accordance with the operation signal. Examples of theoperation of the cryopump system 100, which is performed by the operatorusing the cryopump monitor 130, include the following, and are notlimited thereto.

-   -   The on or off state of the cryopump 10    -   The regeneration start of the cryopump 10 and selection of a        regeneration mode    -   Operations of devices mounted on the cryopump 10 (for example,        opening and closing operations of the rough valve 24, the purge        valve 26, and the vent valve 28 and the change of the operating        frequency of the expander motor 30)    -   Calibration of sensors mounted on the cryopump 10, such as the        pressure sensor 21 (for example, atmospheric pressure adjustment        and zero point adjustment)    -   The on or off state of the compressor 12

As described at the beginning of the present application, it would beconvenient if information related to the cryopump 10 can be seen duringthe operation of the vacuum process device 200. Such information isparticularly useful, when an abnormality occurs in the cryopump system100, in identifying a cause of the abnormality and returning to a normalstate.

However, since existing cryopump products are not provided with such aninformation display tool in many cases, it requires long time to analyzethe abnormality and returning to normal in some cases. In such a case,since the cryopump system 100 is connected to the vacuum process device200, information related to the cryopump system 100 may be availablefrom the vacuum process device 200. However, in reality, the vacuumprocess device 200 is usually not designed to have access to all typesof information related to the cryopump system 100. For this reason, themethod does not necessarily ensure that information necessary foranalyzing the abnormality and returning to normal is available. Inaddition, there can also be a case where a communication abnormalitybetween the host controller 204 of the vacuum process device 200 and thecryopump system 100 is suspected as one of causes of the abnormality.

Thus, a plan to integrally incorporate a display unit that displaysinformation into the cryopump 10 is conceivable. However, even in such acase, in reality, information cannot be seen during operation in manycases. This is because even when the display unit is provided, thedisplay unit is hidden at a place that cannot be seen from the outsidein most cases as the cryopump 10 is housed in the vacuum process device200. In addition, for safety reasons such as avoiding contact withdangers such as a high voltage and a high energy beam used in the vacuumprocess device 200, internal components of the vacuum process device200, such as the cryopump 10, are required to be physically inaccessibleto humans during the operation of the vacuum process device 200. Whenthe operation of the vacuum process device 200 is stopped, the displayunit can be seen by approaching the cryopump 10, but the operation stopof the device is not desirable since the operation stop causes adecrease in productivity.

On the contrary, in the embodiment, the cryopump monitor 130 is disposedoutside the casing 206 of the vacuum process device 200, and informationrelated to the cryopump 10 (and/or the compressor 12) is displayed onthe cryopump monitor 130. For this reason, the operator can easilyconfirm the displayed information related to the cryopump 10 (and/or thecompressor 12) at hand during the operation of the vacuum process device200. Necessary information is available to the operator at a safe placeat any time by looking at the cryopump monitor 130. When an abnormalityoccurs in the cryopump system 100, the operator can quickly proceed toidentification of a cause of the abnormality and returning to the normalstate, using the information obtained from the cryopump monitor 130.

In addition, in the embodiment, the cryopump monitor 130 is connected tothe network 120 without going through the host controller 204. Forexample, the cryopump monitor 130 is connected to the network 120 asbeing directly connected to the cryopump controller 110. Accordingly,even in a case where an abnormality of the host controller 204 or acommunication abnormality between the cryopump controller 110 and thehost controller 204 is suspected, the cryopump monitor 130 can obtaininformation from the cryopump controller 110 and display theinformation. In addition, the cryopump monitor 130 can also obtaininformation that cannot be obtained by going through the host controller204 (information on a cryopump that is not a monitoring target of thehost controller 204) from the cryopump controller 110 and display theinformation.

Further, in the embodiment, the cryopump monitor 130 includes theoperation unit or operation panel 132 for operating the cryopump system100. For this reason, the cryopump system 100 can perform a necessaryoperation from the cryopump monitor 130 apart from operating thecryopump system 100 via the host controller 204 of the vacuum processdevice 200.

The present invention has been described based on the example. It isclear for those skilled in the art that the present invention is notlimited to the embodiment, various design changes are possible, variousmodification examples are possible, and such modification examples arealso within the scope of the present invention.

In the embodiment described above, each of the compressor 12 and thecryopump monitor 130 is individually connected to the cryopumpcontroller 110 by a communication cable (the third communication line123 and the fourth communication line 124). In one embodiment, the thirdcommunication line 123 and the fourth communication line 124 may bealigned by one communication cable branched at an end portion, and thecompressor 12 and the cryopump monitor 130 may be connected to thecryopump controller 110 using the one communication cable.

Instead of directly connecting the cryopump monitor 130 to the cryopumpcontroller 110, the cryopump monitor 130 may be connected to the network120 as being connected to the compressor 12 in a wired manner and bedisposed outside the casing 206 of the vacuum process device 200. Inthis case, the connecting work of the cryopump monitor 130 may beperformed before the operation of the cryopump system 100 or may beperformed during the operation of the cryopump system 100. In addition,the cryopump monitor 130 may be connected to the network 120 as beingconnected to other nodes (for example, the cryopump 10) on the network120, and be disposed outside the casing 206 of the vacuum process device200.

The cryopump monitor 130 may be integrally mounted on the compressor 12.For example, a configuration where the operation panel 62 provided inthe compressor 12 is operated as the cryopump monitor 130 may beadopted.

The cryopump monitor 130 may be capable of switching between enablingand disabling at least some of display functions (and/or operationfunctions). For example, some of the display functions, such asdisplaying internal parameters of the cryopump 10 may be locked by, forexample, a password such that the functions cannot be used in an initialstate of the cryopump monitor 130. The cryopump monitor 130 may enablethe display functions by releasing this lock.

The connection of the cryopump monitor 130 to the network 120 may bewireless. For example, the compressor 12 may be connected to thecryopump controller 110 in a wired manner, and the cryopump monitor 130and the compressor 12 may be wirelessly connected. Since both of thecryopump monitor 130 and the compressor 12 are disposed outside thevacuum process device 200 and are disposed close to each other, carrierwaves for wireless communication are easily transmitted to each otherwell. Alternatively, if possible, the cryopump controller 110 and thecryopump monitor 130 may be wirelessly connected.

In the embodiment described above, the cryopump monitor 130 includes theoperation unit 132, and accordingly, has the operation function of thecryopump system 100. However, in one embodiment, the cryopump monitor130 may have only the display function without having the operationfunction.

At least one cryopump 10 provided in the cryopump system 100 may be acold trap. Typically, the cold trap is cooled by a single-stagecryocooler, is disposed at an inlet of a high vacuum pump, such as aturbo molecular pump, and mainly condenses and exhausts steam on a coldtrap surface. The cryopump monitor 130 may display information relatedto the cold trap.

It should be understood that the invention is not limited to theabove-described embodiment, but may be modified into various forms onthe basis of the spirit of the invention. Additionally, themodifications are included in the scope of the invention.

What is claimed is:
 1. A cryopump system mounted on a vacuum processdevice, the cryopump system comprising: at least one cryopump; acryopump controller that controls the cryopump; a network that connectsthe cryopump to the cryopump controller and transmits informationrelated to the cryopump between the cryopump and the cryopumpcontroller; and a cryopump monitor that is connected to the network anddisplays the information related to the cryopump, which is transmittedvia the network, wherein the cryopump controller is disposed in a casingof the vacuum process device, and the cryopump monitor is disposedoutside the casing of the vacuum process device.
 2. The cryopump systemaccording to claim 1, wherein the cryopump controller is connectable toa host controller provided in the vacuum process device, and thecryopump monitor is connected to the network without going through thehost controller.
 3. The cryopump system according to claim 1, furthercomprising: at least one compressor that is disposed outside the casingof the vacuum process device and is connected to the network, whereinthe cryopump monitor is provided in the compressor.
 4. The cryopumpsystem according to claim 3, wherein the cryopump monitor displaysinformation related to the compressor, which is transmitted via thenetwork.
 5. The cryopump system according to claim 1, wherein thecryopump monitor includes an operation panel that is used for operatingthe cryopump system.
 6. A method of monitoring a cryopump system mountedon a vacuum process device, wherein the cryopump system includes atleast one cryopump, a cryopump controller that is disposed in a casingof the vacuum process device and controls the cryopump, and a networkthat connects the cryopump to the cryopump controller and transmitsinformation related to the cryopump between the cryopump and thecryopump controller, the method comprising: connecting a cryopumpmonitor to the network and disposing the cryopump monitor outside thecasing of the vacuum process device; and displaying the informationrelated to the cryopump, which is transmitted via the network, on thecryopump monitor.